The invention relates to hair dryers in general, and more particularly to improvements in hair dryers of the type wherein an inflatable hood can be coupled to an air supplying apparatus having a housing for an electric motor which drives an impeller to draw atmospheric air into the housing and to cause the atmospheric air to flow past an air heating device in the housing and to thereupon enter the plenum chamber whence it flows through the pores of the inner panel of the chamber and into the hair of the person wearing the hood.
The commonly owned copending patent application Ser. No. 767,413 of Mahlich et al. discloses a hair dryer wherein the housing of the air supplying apparatus is formed with a large number of ports for admission of atmospheric air into the interior of the housing. The ports can be provided in an end wall, in a front wall and in two lateral walls of the housing. Streamlets of air which enter the interior of the housing through such ports are caused to flow into a discrete (separately produced) tubular or frustoconical guide which induces the streamlets to flow toward the impeller of an air conveying unit. The impeller is driven by an electric motor and causes the air to flow into an extension of the hood on its way into the plenum chamber. A suitable air heating unit is provided in the housing to raise the temperature of air to a desired level upstream of the plenum chamber.
An advantage of the hair dryer of Mahlich et al. is that all of the air admitting ports are highly unlikely to become clogged simultaneously, even under the most adverse circumstances, so that the impeller can convey requisite quantities of conditioned air into the hood. The large number of ports entails a reduction of the speed of the streamlets of air which flow into the housing. This is desirable because the person wearing the hood is less likely to be exposed to draft.
The aforementioned guide in the housing of the air supplying apparatus of Mahlich et al. extends substantially all the way from one end wall to the other end wall of the housing, namely from the wall which is remotest from to the wall which is immediately adjacent the impeller. Furthermore, the bearing for the motor which drives the impeller has a rather long tubular component which is telescoped into an elongated portion of the guide. In one embodiment of the hair dryer of Mahlich et al., all of the air which enters the housing by way of numerous ports must enter the guide at one axial end to thereupon flow past the air heating unit and toward the impeller. Certain other embodiments of the hair dryer of Mahlich et al. employ a composite guide which is installed in the housing in such a way that it can admit air at one of its ends as well as at several locations intermediate its ends. The making and installation of a discrete guide particularly a composite guide, contribute to the initial and assembly cost of the hair dryer.